Rod outer segment maintenance is enhanced in the presence of BFGF, CNTF and GDNF

  • Carwile M
  • Culbert R
  • Sturdivant R
 et al. 
  • 17

    Readers

    Mendeley users who have this article in their library.
  • 55

    Citations

    Citations of this article.

Abstract

We employed a morphological assay of outer segment collapse to determine if growth factors or other supplements directly affect dissociated rod photoreceptors in vitro. The morphological changes in outer segments were correlated with the light responsiveness of rods. Time-lapse video microscopy was used to observe the collapse of rod outer segments from isolated single cells and small clumps of cells. A consistent pattern of outer segment collapse into the inner segment was observed, yielding a convenient assay of the effects of neurotrophic factors on photoreceptor functional maintenance. The functional state of rods, defined as light-responsiveness, was measured with suction electrode recordings and matched with the various stages of outer segment collapse. Ciliary neurotrophic factor (CNTF) and glial cell-line-derived neurotrophic factor (GDNF) at a high concentration, yielded statistically significant improvements in rat outer segment survival times. Basic fibroblast growth factor (bFGF), which rescues photoreceptors in several rodent models of retinal degeneration, produced a significant increase in survival time in the presence of the cofactor heparin. In 4 out of 10 cases using human tisue, bFGF also yielded a significant increase in survival times. When brain-derived neurotrophic factor (BDNF) was applied to rat rods, outer segment survival times did not change. Outer segments collapsed more quickly when either pigment epithelial cell derived factor (PEDF) or sugar N- acetyl v-galactosamine (NAD-gal) were present. Our results show that rod photoreceptors can respond to bFGF, GDNF and CNTF in vitro and provide evidence for a direct effect of these neurotrophic factors on rods. The rapid collapse of isolated photoreceptors in this model provides a convenient means for testing various neurotrophic agents and the induced cellular responses.

Author-supplied keywords

  • BDNF
  • BFGF
  • CNTF
  • GDNF
  • Growth factor
  • Human
  • PEDF
  • Photoreceptor
  • Rat
  • Retina
  • Rod

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Authors

  • Mary E. Carwile

  • Richard B. Culbert

  • Rachel L. Sturdivant

  • Timothy W. Kraft

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free